1. Field of the Invention
The present invention is related to a display system for generating three-dimensional images and method thereof, and particularly to a display system for generating three-dimensional images that alternately utilizes a set of square-wave voltages and a direct current voltage to adjust refraction angles of a plurality of liquid crystals of a liquid crystal lens for suppressing an optical nebulization phenomenon and method thereof.
2. Description of the Prior Art
Please refer to FIG. 1. FIG. 1 is a diagram illustrating an alternating current square wave voltage 100 for driving a plurality of liquid crystals of a traditional liquid crystal lens according to the prior art. As shown in FIG. 1, a frequency of the alternating current square wave voltage 100 is 1 KHz and an amplitude of the alternating current square wave voltage 100 is 1V. But, frequency range of the alternating current square wave voltage 100 can be between 240 Hz and 1 KHz, and the amplitude of the alternating current square wave voltage 100 varying with different liquid crystal lenses changes from ±1V to ±100V.
Please refer to FIG. 2A, FIG. 2B and FIG. 2C. FIG. 2A is a diagram illustrating a display system 200 according to the prior art, FIG. 2B is a diagram illustrating the display system 200 outputting a two-dimensional image, and FIG. 2C is a diagram illustrating the display system 200 outputting a three-dimensional image. As shown in FIG. 2A, the display system 200 includes a liquid crystal panel 202, a driving voltage generation circuit 204, and a liquid crystal lens 206. The liquid crystal panel 202 is used for receiving a three-dimensional image signal and a two-dimensional image signal, and outputting a three-dimensional image and a two-dimensional image. As shown in FIG. 2B, when the liquid crystal panel 202 outputs the two-dimensional image, the driving voltage generation circuit 204 generates a 0V direct current driving voltage according to the two-dimensional image signal. Then, the liquid crystal lens 206 outputs the two-dimensional image according to the 0V direct current driving voltage. That is to say, the plurality of liquid crystals of the liquid crystal lens 206 do not refract the two-dimensional image, so a left eye and a right eye of a watcher simultaneously receive the same two-dimensional image. As shown in FIG. 2C, when the liquid crystal panel 202 outputs the three-dimensional image, the driving voltage generation circuit 204 generates an alternating current square wave driving voltage according to the three-dimensional image signal. The liquid crystal lens 206 outputs the three-dimensional image according to the alternating current square wave driving voltage. That is to say, the plurality of liquid crystals of the liquid crystal lens 206 refracts a left eye image of the three-dimensional image to the left eye of the watcher, and a right eye image of the three-dimensional image to the right eye of the watcher.
Please refer to FIG. 3A, FIG. 3B and FIG. 3C. FIG. 3A is a diagram illustrating the display system 200 displaying a Moire pattern when the display system 200 displays the three-dimensional image, FIG. 3B is a diagram illustrating the display system 200 generating an optical nebulization phenomenon when the display system 200 displays the Moire pattern, and FIG. 3C is a diagram illustrating a relationship between three-dimensional image crosstalk and a view angle when the display system 200 displays the three-dimensional image. As shown in FIG. 3A, when the left eye of the watcher is located at a right eye image area of the three-dimensional image displayed by the display system 200, and the right eye of the watcher is located at a left eye image area of the three-dimensional image displayed by the display system 200, the watcher can see the Moire pattern. As shown in FIG. 3B and FIG. 3C, after the display system 200 displays the Moire pattern for a period of time, the three-dimensional image displayed by the liquid crystal panel 202 through the liquid crystal lens 206 may show the optical nebulization phenomenon, resulting in the three-dimensional image crosstalk being increased. Therefore, the prior art for driving the liquid crystal lens 206 according to the alternating current square wave driving voltage may worsen quality of the three-dimensional image displayed by the liquid crystal panel 202 through the liquid crystal lens 206.